ASTM A333/A333M — Seamless and welded steel pipes for low temperature applications
Grades
Gr.1(-45℃), Gr.3(-100℃, 3.5Ni), Gr.4(-75℃), Gr.6(-45℃), Gr.7(-100℃, 2.25Ni), Gr.8(-196℃, 9Ni), Gr.9(-100℃, 3.5Ni), Gr.10(-50℃), Gr.11(-60℃)
Chemical composition and mechanical properties
| Grade | Chemical composition | Mechanical properties |
|---|---|---|
| Gr.1 | C≤0.30, Mn 0.40-1.06, P≤0.025, S≤0.025 | Rm ≥380 MPa, Rp0.2 ≥205 MPa, A≥30% (longitudinal), Akv≥18J at -45℃ |
| Gr.3 | C≤0.19, Mn≤0.70, P≤0.025, S≤0.025, Ni 3.18-3.82 | Rm ≥450 MPa, Rp0.2 ≥240 MPa, A≥30% (longitudinal), Akv≥18J at -100℃, normalizing |
| Gr.4 | C≤0.12, Mn 0.50-1.05, P≤0.025, S≤0.025, Si 0.08-0.37, Ni 0.47-0.98, Cr 0.44-1.01, Mo≤0.12, Cu 0.40-0.75, Al 0.04-0.30, Nb 0.02-0.05 | Rm ≥415 MPa, Rp0.2 ≥240 MPa, A≥30% (longitudinal), Akv≥18J at -75℃ |
Application scope
ASTM A333/A333M specifies seamless and welded steel pipes for cryogenic applications, including multiple grades from Gr.1 to Gr.11, covering carbon steel, nickel alloy steel and 9Ni steel. As the grade increases, the low-temperature impact toughness is enhanced and it is adapted to extremely low temperature conditions. It is widely used for cryogenic media transportation and pressure-bearing welded pipelines.
Typical applications
Widely used in LNG pipelines, ethylene plants and cryogenic storage tank inlet and outlet pipes, as well as in refrigeration systems, polar engineering pipelines and cryogenic process pipelines and gathering and transportation pipelines. The appropriate grade can be selected according to the lowest operating temperature to form a welded cryogenic pressure transportation pipeline system, which can serve stably in cryogenic and extremely cold environments for a long time and ensure transportation safety.
